Add ability to configure headers in RemoteTermServiceProvider configuration

[csandersdev]

Is your feature request related to a problem? Please describe.
I want to be able to target a specific tenant on an IBM FHIR instance as the terminology provider for a multi-tenant system. My idea is to use the remoteTermServiceProvider to achieve that, but it is not possible right now to pass headers and thus target a specific tenant.

Describe the solution you'd like
I would like the ability to configure header information in the remoteTermServiceProvider configuration which will be passed to the FHIRClient during execution time.

Describe alternatives you've considered
We could set it up so that there is a separate FHIR server cluster that serves terminology from the default tenant instead of using a tenant within our patient data server cluster and that would avoid the need to pass the tenant ID header.

Acceptance Criteria

1. GIVEN a multi-tenant fhir server installation
   AND separate data and terminology tenants exist
   AND configuration properties exist for configuring headers in the remoteTermServerProvider configuration exist
   WHEN the user configures the remoteTermServiceProvider to point to the localhost with a specific tenant-id header
   THEN terminology data is leveraged from the separate tenant.

Additional context
Add any other context or screenshots about the feature request here.

[lmsurpre]

@CoreySandersOH this is merged into main and set to go out with the 4.8.3 release. Do you mind having a quick look and confirming it addresses your request?

[csandersdev]

LGTM